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    Ack, I hate that this exam has so much emphasis on amines in it. It's like, if you know your amine reactions you get an extra 10-20 marks :-(
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    (Original post by Strawberry x3)
    4/4/6 I think
    damn i thought it was 4,5,6
    Thank you
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    (Original post by mrmccarl)
    anyone else feeling depressed after that C4 maths exam?
    I am, Edexcel? I need 88/100. Not sure if I got it. :/
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    (Original post by otrivine)
    http://www.ocr.org.uk/Images/59704-m...lysis-june.pdf

    question 2)c)i

    why do they not put on both sides O-Na+

    is because it can form no charge overall?
    I think its an ionic compound isnt it?
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    I made some flashcards for my self to help learn the synthesis reactions, if anyone is having trouble remembering they may help you (Im fairly sure all of the reactions are right, if there is anything Ive missed or got wrong let me know and ill change it)
    http://getrevising.co.uk/revision-te...ype=flashcards
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    (Original post by Sly1)
    I think its an ionic compound isnt it?
    How do you know if its ionic?
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    A* (81 UMS) raw marks needed /60

    June 10 47
    Jan 11 49
    June 11 49
    Jan 12 53
    June 12 49
    Jan 13 55

    i am quite concerned at the jan 13 very high raw mark for an A*,because it looks even harder than previous years exams. but bear in mind that there was increased time allowed for this paper by 15 minutes, it just seems like a really high raw mark for an A* when the paper is harder.More and more people are doing really well in this exam. on a personal note i need about 81 ums in this exam to get an A*, but it will be difficult!
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    (Original post by otrivine)
    How do you know if its ionic?
    Don't over think. I don't know either maybe someone else can direct you to your answer ..
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    Compare the structures of saturated fats,unsaturated fats and fatty acids.
    Anyone??
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    Can someone tell me if i've got this right?

    Testing for aldehydes/ketones

    Brady's reagent/ 2,4-dinitrophenylhydrazine
    Aldehyde - orange precipitate
    Ketone - orange precipitate
    Carboxylic acid - no change

    Tollen's reagent
    Aldehyde- silver mirror/ag formed
    Ketone - none
    C acid- none

    Acidifies pottassium dichromate
    ketone-none
    aldehyde-orange to green
    c acid- none
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    anyone know how to go from an AMINE to an AMIDE
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    (Original post by otrivine)
    quick question

    http://www.ocr.org.uk/Images/65129-q...d-analysis.pdf

    why is it only aspirin reacts with the Na2CO3 cause both compounds consist of carbonyl groups/?
    Its to do with the fact COOH implies an acid and Acid + carbonate --> Salt + CO2 + H20

    whereas paracetamol contains OH (not an acid)
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    (Original post by mrmccarl)
    anyone else feeling depressed after that C4 maths exam?
    Yes very :-( Trying not to let it affect chem revision as I have lots to get through with so little time :/
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    (Original post by Myocardium)
    Can someone tell me if i've got this right?

    Testing for aldehydes/ketones

    Brady's reagent/ 2,4-dinitrophenylhydrazine
    Aldehyde - orange precipitate
    Ketone - orange precipitate
    Carboxylic acid - no change

    Tollen's reagent
    Aldehyde- silver mirror/ag formed
    Ketone - none
    C acid- none

    Acidifies pottassium dichromate
    ketone-none
    aldehyde-orange to green
    c acid- none
    it is perfect, but remember that Brady's reagent is 2,4-dinitrophenylhydrazine +sulphuric acid and methanol
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    (Original post by ofudge)
    Its to do with the fact COOH implies an acid and Acid + carbonate --> Salt + CO2 + H20

    whereas paracetamol contains OH (not an acid)
    phenol is a weak acid
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    (Original post by ofudge)
    Its to do with the fact COOH implies an acid and Acid + carbonate --> Salt + CO2 + H20

    whereas paracetamol contains OH (not an acid)
    I see, and http://www.ocr.org.uk/Images/59707-q...d-analysis.pdf

    3)c)i) I did both sides O-Na+ but mark scheme says award 1 mark not 2 ? why
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    ok so basically ammonia is nh3, amine is nh2, and amide is just nh? im unsure about amide because i know an amide bond is c=o bonded to nitrogen thats bonded to a hydrogen....
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    also guys which paper do you recommend is the hardest??? i have done every paper from 08 to present 3 times over as i need 83 ums for a*.
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    (Original post by Zzzyax)
    it is perfect, but remember that Brady's reagent is 2,4-dinitrophenylhydrazine +sulphuric acid and methanol
    when answering a question like 'a test for aldehydes' can you say 2,4dnp or do you have to say bradys reagant
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    (Original post by mrmccarl)
    also guys which paper do you recommend is the hardest??? i have done every paper from 08 to present 3 times over as i need 83 ums for a*.
    june 10
 
 
 
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